The chances of survival for a South Gwinnett grad fighting for her life after a zip-lining accident are "slim to none," her father posted on Facebook Tuesday afternoon.

Aimee Copeland -- a 24-year-old master's student at the University of West Georgia -- was zip-lining near Carrollton on May 1 when her line broke and she fell. An initial trip to the hospital led to 22 staples in her left leg, but she was released.

Persistent pain, though, caused Copeland to return to the hospital Friday. She was ultimately diagnosed with necrotizing fasciitis -- a flesh-eating bacteria that can destroy fat, skin and muscle. She was life-flighted to the Joseph M. Still Burn Center in Augusta, where her leg was amputated and skin removed from her abdomen, her father, Andy Copeland, posted on Facebook.

Andy Copeland posted Monday that his daughter was in critical condition but "responding and making gradual improvement." That took a turn for the worse Tuesday.

In a post Tuesday afternoon, Copeland said his daughter was continuing to "experience a major shutdown of all five major organs." Aimee's temperature was up to 102 degrees and she was relying on a respirator to breath, he said.

"The doctor was careful to set expectations this morning: Aimee's survival chances are 'slim to none,'" he wrote.

Attempts to reach the Copelands directly were unsuccessful. It was unclear where she was zip-lining during her accident, or what caused the line to break.

Aimee Copeland is a graduate of South Gwinnett High School and received her bachelor's degree from the University of Georgia in 2010. She is nearing the completion of her master's degree in psychology at the University of West Georgia.

A post on the school's unofficial student website described Aimee Copeland as a "bright star, lover of life, infinitely generous of heart and spirit."

Her father urged friends and well-wishers to keep their spirits up through tragedy. He urged the public the keep praying and reach out to friends to do so as well.

"If this news leaves you with a long face, then wipe that look off right now," he wrote. "Smile and honor Aimee with your hope. Shower my child with prayers and good vibes. I know that's how she would want it."

Andy Copeland also urged well-wishers to donate blood in his daughter's honor.

"If everyone reading this will go and donate one pint of your blood," he wrote, "then that will help my daughter and many more like her."